Inside Apple's Intel iMac

A first look at the new Intel iMac from Computerworld.

Quick Mac riddle: What looks like an iMac G5, sounds like an iMac G5 when it starts up, and feels faster than a Power Mac G5?

Answer: The new Intel-based iMac from Apple.

For now, those interested in an Intel experience with an Apple flair will have to make do with the new iMac, unveiled by Apple CEO Steve Jobs to much fanfare last month. Two models are available: the 17-inch version, which sells for £929 and has the Intel Core Duo 1.83GHz chip inside, and the larger, 20-inch version, which goes for £1,299 and has a slightly faster 2GHz Core Duo processor. Both ship with 512MB of PC2-5300 (667MHz) DDR2 RAM and either a 160GB or 250GB hard drive. And both ship with Apple's two-button mouse, in and of itself a nice addition.

So how does the new iMac fare in regular use? This latest generation of Apple's all-in-one runs circles around its predecessor - most of the time.

23-second start-up

Just how fast is the new iMac? We're talking about a start-up time from Mac chime to desktop of just 23 seconds. That's faster than my own Power Mac G5 with dual 2.7GHz processors. Apple applications like Safari and iPhoto start up before their icons have bounced twice in the dock. In fact, this iMac is faster on those admittedly informal benchmarks than any Mac I've ever played with - I mean, used.

Now, I realise start-up times do not a user experience make. But they are an indicator of the potential for Apple as it moves its hardware line over to Intel processors during the year ahead. And, as is often the case with such transitions, there are a few speed bumps. In this case, that would be all of the programs that have yet to be rewritten as "universal" apps that can run on the Intel hardware as well as on Apple's older G3, G4 and G5 processors.

To deal with the transition, Apple created Rosetta, the nifty translation software now built into Mac OS X. Rosetta allows applications coded for PowerPC processors to run on the new iMacs seamlessly, albeit a bit more sluggishly. It is, after all, emulation software, and it does exact a speed penalty.

See the potential

For now, Apple officials are rightfully choosing to accentuate the positive when it comes to the new iMac. In a recent interview, Tom Boger, senior director for desktop product marketing at Apple talked up the iMac's Core Duo 2GHz processor. In essence, the dual-core chip gives the iMac two processors on the same bit of silicon, which makes for speedy computing when used with programs designed to take advantage of all that processing power - like Mac OS X and many of Apple's own programs.

The biggest change in the new iMac "first and foremost is the processor," Boger said. "I think the key there with the Intel Core Duo, what makes it unique in the marketplace from a processor standpoint is that it's giving us this dual-core performance. But unlike other dual-core processors, it does so with low power consumption."

Low power consumption equals low heat, which means the iMac's cooling fans don't need to run as often, resulting in a quiet machine, he said.

"The other benefit is the performance," Boger said.

He pointed to Apple tests that showed the iMac to be two to three times faster than earlier models in integer and floating processor benchmarks: "We tested it two ways. We ran industry-standard benchmarks. SPEC has two types of tests - the integer [test] was three times faster, and floating point was twice as fast. That shows the potential of what the architecture can do."

Faster processes as Universal plans emerge

Other iMac owners have reported online that while the new hardware is noticeably faster when using Apple's universal apps, it's not two or three times faster than its predecessor. Asked about that disparity, Boger said: "This was a process, not a point in time. We got our hands on about six different universal apps in some cases the public hasn't. These apps represent all kinds of things. Virtually every day now people are announcing their plans for universal apps. I'm very confident [users are] going to start seeing performance that's impressive."

He noted that a still-unreleased version of Doom 3 was 2.3 times faster in terms of frames per second than it was on earlier iMacs, and said that photo-editing features in iPhoto, such as converting a picture from color to black and white, is twice has fast. Safari, Boger said, loads pages 1.6 times faster than on earlier hardware, while Apple's Pages application is 1.9 times as fast.

The speed increases are the result of more than just the addition of the Core Duo processor. Apple has also beefed up the video RAM with the ATI X1600 video card and faster RAM. And as has been the case for years, Mac OS X itself is designed to take advantage of multiple processors, Boger said.

"We've been shipping dual-processor Macs for quite some time now," he said. "So Mac OS X has been designed from the ground up to take advantage of dual processors. That was an advantage right from the beginning. A key difference is that this version of Mac OS X is native on Intel. I'm talking about the entire operating system, every Apple application, every utility, they are all native now.

"Developers are almost on a daily basis making announcements on their universal apps. We're obviously just trying to work with them to release universal applications as quickly as possible," he said. "It just takes time for the developer community and engineers to become familiar with the new architecture."

Until that happens, Boger said, "Rosetta, obviously, is absolutely key technology. It's the software translation technology that ships with every iMac and allows our customers to transition to Intel-based Macs. It just runs like you'd expect; there's no user interface change."

More memory matters

One change from the previous iMac is that Apple now recommends users who want to change their hard drive - or make other under-the-hood upgrades - get a qualified service provider to do the work. Owners can still easily access the iMac's RAM slots, which are located behind a small door at the base of the machine.

Note to would-be iMac owners: spring for more RAM. Although the iMac comes with 512MB installed, adding another 512MB or even a 1GB module, will make using Apple's Mactel machine even more enjoyable.

So at first glance, is the new iMac all it should be? I'd say yes, although if you're heavily dependent on non-universal apps, you might want to wait until your favourite must-have program has been recoded. Of course, if you're like me, waiting will be the hardest part. And should you decide to plunk down your money now at the nearest Apple store, well, you won't be disappointed when you get your new iMac home.